What I took away was that time in the gym didn't get you any further than time on the bike.

That conclusion would still leave some room for winter weight training, if the weight training is in addition to the time you can spend on the bike. For example, if the amount of time you can ride during the weekdays is limited by available daylight, and tolerence for the trainer, then it could still make sense to supplement your hour on the trianer with some weight lifting.